CVE-2026-9087

HIGHNVD 8.16.4▼
EchelonGraph scoreMEDIUM confidence

Score 6.4 from GitHub Security Advisory published 2026-05-20. NVD baseline CVSS 8.1; sources differ by 1.7.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
8.1
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS: 0%CVSS: 8.1Exploit: NoneExposed: 0

A fix is available — apply it.

A flaw was found in Keycloak. The cross-session verification proof is keyed only by (local userId, idpAlias) and is not bound to the upstream identity that was actually verified, so a second upstream account on the same IdP can consume it and get linked to the victim's local account.

CVSS v3
8.1
EG Score
6.4(medium)
EG Risk
—
EPSS
23.4%
KEV
Not listed

Published

May 20, 2026

Last Modified

June 26, 2026

Advisory Details (2)

Auto-updated Jun 10, 2026
Patch available. Sources: redhat.
redhat

2480172 – (CVE-2026-9087) CVE-2026-9087 keycloak: Cross-Session Email Verification Proof Not Bound to Upstream Identity in First-Broker-Login

https://bugzilla.redhat.com/show_bug.cgi?id=2480172
redhat Patch Available

cve-details

https://access.redhat.com/security/cve/CVE-2026-9087

Vendor Advisories for CVE-2026-9087(5)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Patch Availability(3)

Vendor / EcosystemFixed in / PatchReleasedSource
redhatrhbk/keycloak-rhel92026-06-25redhat
redhatrhbk/keycloak-rhel9-operator:26.4-192026-06-25redhat
redhatrhbk/keycloak-rhel9-operator:26.6-62026-06-10redhat

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Affected Packages

(1 across 1 ecosystem)
Maven(1)
PackageVulnerable rangeFixed inDependents
org.keycloak:keycloak-services1.0-alpha-1 ... 9.0.3 (227 versions)26.6.3—

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 8× in last 7d / 36× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-07-22 14:08 UTCEPSS rescore
  2. 2026-07-21 15:25 UTCEPSS rescore
  3. 2026-07-21 15:25 UTCEPSS rescore
  4. 2026-07-20 17:08 UTCEPSS rescore
  5. 2026-07-19 14:31 UTCEPSS rescore
  6. 2026-07-19 02:29 UTCEPSS rescore
  7. 2026-07-18 10:04 UTCEPSS rescore
  8. 2026-07-16 17:03 UTCEPSS rescore
  9. 2026-07-15 16:57 UTCEPSS rescore
  10. 2026-07-15 02:00 UTCEPSS rescore
  11. 2026-07-13 22:31 UTCEPSS rescore
  12. 2026-07-13 06:13 UTCEPSS rescore
  13. 2026-07-12 05:46 UTCEPSS rescore
  14. 2026-07-11 08:27 UTCEPSS rescore
  15. 2026-07-09 19:10 UTCEPSS rescore
  16. 2026-07-08 15:16 UTCEPSS rescore
  17. 2026-07-07 13:46 UTCEPSS rescore
  18. 2026-07-06 16:27 UTCEPSS rescore
  19. 2026-07-06 02:23 UTCEPSS rescore
  20. 2026-07-05 02:31 UTCEPSS rescore
  21. 2026-07-05 02:30 UTCEPSS rescore
  22. 2026-07-04 06:31 UTCEPSS rescore
  23. 2026-07-04 06:31 UTCEPSS rescore
  24. 2026-07-01 15:07 UTCEPSS rescore
  25. 2026-06-30 23:22 UTCEPSS rescore
Show 64 more
  1. 2026-06-29 20:26 UTCVendor advisory
  2. 2026-06-29 14:06 UTCEPSS rescore
  3. 2026-06-28 14:07 UTCEPSS rescore
  4. 2026-06-28 04:56 UTCEPSS rescore
  5. 2026-06-27 20:13 UTCVendor advisory
  6. 2026-06-27 03:08 UTCEPSS rescore
  7. 2026-06-26 19:33 UTCVendor advisory
  8. 2026-06-25 15:09 UTCVendor advisory
  9. 2026-06-25 13:50 UTCEPSS rescore
  10. 2026-06-24 14:05 UTCEPSS rescore
  11. 2026-06-23 21:33 UTCEPSS rescore
  12. 2026-06-22 14:25 UTCEPSS rescore
  13. 2026-06-21 14:56 UTCEPSS rescore
  14. 2026-06-21 01:59 UTCEPSS rescore
  15. 2026-06-19 19:26 UTCEPSS rescore
  16. 2026-06-18 17:52 UTCEPSS rescore
  17. 2026-06-18 02:02 UTCVendor advisory
  18. 2026-06-17 17:53 UTCEPSS rescore
  19. 2026-06-17 00:30 UTCVendor advisory
  20. 2026-06-16 17:53 UTCEPSS rescore
  21. 2026-06-16 00:37 UTCVendor advisory
  22. 2026-06-15 17:49 UTCEPSS rescore
  23. 2026-06-15 17:49 UTCEPSS rescore
  24. 2026-06-15 00:46 UTCVendor advisory
  25. 2026-06-14 23:18 UTCEPSS rescore
  26. 2026-06-14 00:52 UTCVendor advisory
  27. 2026-06-13 23:00 UTCEPSS rescore
  28. 2026-06-13 01:02 UTCVendor advisory
  29. 2026-06-12 23:12 UTCEPSS rescore
  30. 2026-06-12 23:12 UTCEPSS rescore
  31. 2026-06-12 01:10 UTCVendor advisory
  32. 2026-06-11 14:00 UTCEPSS rescore
  33. 2026-06-11 01:19 UTCVendor advisory
  34. 2026-06-11 01:19 UTCGHSA enrichment
  35. 2026-06-10 22:19 UTCEPSS rescore
  36. 2026-06-10 13:22 UTCEPSS rescore
  37. 2026-06-10 01:28 UTCGHSA enrichment
  38. 2026-06-09 01:38 UTCGHSA enrichment
  39. 2026-06-08 23:31 UTCNVD updateCVSS v3 → 8.1 · severity → HIGH
  40. 2026-06-08 14:17 UTCEPSS rescore
  41. 2026-06-08 01:47 UTCGHSA enrichment
  42. 2026-06-07 15:25 UTCEPSS rescore
  43. 2026-06-07 01:57 UTCGHSA enrichment
  44. 2026-06-06 13:47 UTCEPSS rescore
  45. 2026-06-06 02:06 UTCGHSA enrichment
  46. 2026-06-05 22:47 UTCEPSS rescore
  47. 2026-06-05 06:10 UTCEPSS rescore
  48. 2026-06-05 02:16 UTCGHSA enrichment
  49. 2026-06-04 13:12 UTCEPSS rescore
  50. 2026-06-04 02:25 UTCGHSA enrichment
  51. 2026-06-03 02:33 UTCGHSA enrichment
  52. 2026-06-02 20:13 UTCEPSS rescore
  53. 2026-06-02 02:42 UTCGHSA enrichment
  54. 2026-06-01 13:52 UTCEPSS rescore
  55. 2026-06-01 02:51 UTCGHSA enrichment
  56. 2026-05-31 22:30 UTCEPSS rescore
  57. 2026-05-31 00:16 UTCEPSS rescore
  58. 2026-05-29 13:44 UTCEPSS rescore
  59. 2026-05-28 13:44 UTCEPSS rescore
  60. 2026-05-27 13:40 UTCEPSS rescore
  61. 2026-05-26 13:44 UTCEPSS rescore
  62. 2026-05-26 07:18 UTCEPSS rescore
  63. 2026-05-21 22:43 UTCEPSS rescore
  64. 2026-05-20 17:36 UTCEG score recompute

Related CVEs(same vendor + same CWE)

Frequently asked(5)

What is CVE-2026-9087?
CVE-2026-9087 is a high vulnerability published on May 20, 2026. A flaw was found in Keycloak. The cross-session verification proof is keyed only by (local userId, idpAlias) and is not bound to the upstream identity that was actually verified, so a second upstream account on the same IdP can consume it and get linked to the victim's local account.
When was CVE-2026-9087 disclosed?
CVE-2026-9087 was first published in the National Vulnerability Database on May 20, 2026, with the most recent update on June 26, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-9087 actively exploited?
CVE-2026-9087 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 23.4% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-9087?
CVE-2026-9087 has a CVSS v3 base score of 8.1 (NVD). EchelonGraph synthesises NVD + CISA KEV + FIRST EPSS + GHSA into a combined EG score of 6.4.
How do I remediate CVE-2026-9087?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-9087, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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